盐酸氨基脲的研制

Research on the Preparation of Semicarbazide Hydrochloride

以水合肼和尿素为原料,经缩合而得氨基脲液,降温到50℃以下后加入盐酸进行酸化络合,再冷却结晶得到盐酸氨基脲粗品,粗品经洗涤、抽滤、烘干后即为产品。实验分析了反应温度、投料及反应时间和配料比等因素对盐酸氨基脲收率的影响,并对盐酸氨基脲的组成和结构进行了测定分析。实验表明,反应温度为102℃,四次投料量之比为4:3:2:1,投料间隔时间为45min,水合肼、尿素与盐酸的摩尔比为1:1.52:1.80时,盐酸氨基脲的收率可达87.6%,纯度可达99.0%以上。

Semicarbazide was condensed by hydrazine hydrate and urea. Then added hydrochloric acid into it when temperature was dropped below 50℃, and it should be acidified. They cooled and crystallized, then synthesize the crude product of semicarbazide hydrochloride. The crude product was cleaned through wash, filtration and drying. Many influential factors on the yield of semicarbazide hydrochloride such as reaction temperature, feeding, reaction time and the mole ratio of materials were analyzed. The composition and configuration of semicarbazide hydrochloride were determined and analyzed also. The experiment results indicated： under such condition as reaction temperature of 102℃, four feedings mole ratio of 4 ： 3 ： 2 ： 1, the intervial between two feedings of 45 min, hydrazine hydrate, urea and hydrochloric acid mole ratio of 1 ： 1.52 ： 1.80, the yield of semicarbazide hydrochloride could reach 87.6% and the purity of the product could reached above 99.0%.